Perhaps you should try some spelling variations:
va hanh » van hanh, va thanh, va danh
dai hoi » dai hoc, dai moi
hieu su » hieu sau, tieu su, hieu so
dai hai » dai han, dai tai, dai thao
vi cua » vai cua, di cua
xuc va » duc va, tuc va, luc va
su cam » su nam, su cao, su can
cua te » cua tu
sac ky » cac ky

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sai ky) or (sac ky)) sang ((dai hoi) OR (dai hai)). hieu su cam xuc va hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sai ky) OR (sac ky)) sang ((dai hoi) OR (dai hai)). hieu su cam xuc va hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sai ky) or (sac ky)) sang ((dai hoi) OR (dai hai)). hieu su cam xuc va hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: tu ((sai ky) or (sac ky)) sang ((dai hoi) OR (dai hai)). hieu su cam xuc va hanh vi cua te*.